This revised proposal requests the purchase of a Bio-Rad MRC-1024 system to be used by 7 Faculty at the University of Texas Medical Branch, all with NIH-supported funding in the field of Neuroscience or Neuroendocrinology. The funded projects require: 1) an upright light- microscope assembly, 2) lasers with excitation in the 488nm, 568nm and 633nm laser excitation range (which allow imaging in green, yellow/red and far red, 3) ability to merge two fluorescent markers onto one image in three dimensions, 4) ability to superimpose fluorescent images onto black and white images of histological material 5) relatively user friendly software, 6) history of support from the vendor and 7) users within the Houston-Galveston community who could help form a users' support group. The Bio-Rad NRC-1024 system plus our local committee meets all these requirements. We emphasize that the proposal includes plans for scheduling, maintenance and upgrades as well as plans for technological development of applications such as stereology. Each of the funded research projects will be extended and expanded by this Bio-Rad system. In addition, one area where technological advances might be made by our group is in the wedding of this technology to stereological principles. Thus, acquisition of this technology should materially advance knowledge in fields of neuroanatomy and neuroendocrinology, with particular reference to basic pain mechanisms, and regulation of reproductive systems and also in applications where the combination of confocal and electron microscopic analyses become important.